Stock feed mechanism for bar machines



Nov. 17, 1953 A; H. JOBERT STOCK FEED MECHANISM FOR BAR MACHINES 4 Sheets-Sheet 1 Filed April 22, 1948 INVENTOR I ARTHUR H. JOBERT ATTORNEYS Nov. 17, 1953' A. H. JOBERT STOCK FEED MECHANISM FOR BAR MACHINES 4 Sheets-St xeec. 2

Filed April 22. 1948 INVENTOR ARTHUR H. JOBERT ATTORNEYS NOV. 17, 1953 JQBERT 2,659,127

STOCK FEED MECHANISM FOR BAR MACHINES Filed April 22, 1948 4 Sheets-Sheet 3 ATTORNEYS Nov. 17, 1953 I A. H. JOBERT STOCK FEED MECHANISM FOR BAR MACHINES 4 Sheets-Sheet 4 Filed April 22. 1948 FIG. 8.

INVENTOR ARTHUR H. JOBERT' ATTORNEYS Patented Nov. 17, 1 953 STOCK FEED MECHANISM FOR BAR MACHINES Arthur H. J obert, New Britain, Conn., assignor to The New Britain Machine Company, New Britain, Conn., a corporation of Connecticut Application April 22, 1948, Serial No. 22,655

My invention relates to automatic rotating machines, such as automatic screw machines, and in particular to a stock-feeding mechanism therefor.

It is an object of the invention to provide an improved machine of the character indicated.

It is another object to provide an improved feed mechanism for a machine of the character indicated.

It is a vfurther object to provide an improved means for automatically shutting down a part of the machine when automatically fed stock has been consumed to a point beyond which no further use may be made of the piece being fed.

It is an additional object to provide an improved automatic stop mechanism for a machine with an adjustable feed, wherein feed adjustments may be made without in any way touching or affecting the stop mechanism.

It is also an object to provide an improved feed shut-off mechanism in an indexing machine of the character indicated, wherein the feed will not beshut ofi until the last usable section of a piece of stock has been fully worked and until the station which need stock replenishment has been indexed into a stock-feed position.

It is a still further object to provide an imfollowing specification in conjunction with the accompanying drawings. In said drawings,

which show, for illustrative purposes only, a preferred form of the invention:

Fig. l is a side elevation of a machine incorporating features of the invention;

Fig. 2 is an enlarged fragmentary sectional view taken substantially in the plane 2-2 of Fig. 1;

Fig. 3 is a sectional view taken more or less along the line 33 of Fig. 2;

Fig. 4 is an enlarged. fragmentary view in elevation, taken from the rear end of the machine of Fig. 1, looking forward, and omitting certain frame parts;

Fig. 5 is an enlarged fragmentaryidetail of a 9 Claims. (Cl. 29-62) 2 portion of Fig. 3, with the parts shown in a different relationship;

Fig. 6 is a right-end view of parts of Fig. 5;

Fig. '7 is a view of the underside of the feedslide means of Fig. 4, as seen from the plane 1-? of Fig. 4; and

Fig. 8 is a schematic showing illustrating certain features of the automatic operation of my machine.

Briefly stated, my-invention contemplates an improved stock-feed mechanism for a machine of the character indicated. The feed mechanism may employ conventional feed-cam and feedfinger means, but I interpose novel means responsive to failure of the feed-finger means to maintain grasping contact with the stock which is being fed; upon disengagement of the feedfinger means from the stock, the feed means may be effectively disabled. In the indexing machine in connection with which apreferred form is to be disclosed, this disabling. is arranged to occur afterthe last usable piece of stock has been completely worked (i. c. after cut-off) and when the collet' or chuck containing the useless piece of stock isv positioned for stock feeding. In addition to such automatic operation, the stock-feed mechanism may also be disabled at will, if desired.

Referring to the drawings, my invention is shownin application to a multiple-station indexing machine which may bean automaticrbar machine. The machine is shown to include a plurality of spindles Iii-I ll2,l3-l4 revolu-' bly supported in an indexible spindle carrier 15 within the case 16 at the rear end of the machine. The machine may include a number of forming slides (not shown) for forming and cut-off operations when the spindles i0 through i 4 are at the Various indexed stations of the machine. For end-working operations tools may be mounted at. various positions on a slide ll reciprocable on an arbor I8 carried by the spindle carrier l5 and case IS. A stock stop 20 may be located opposite, one of the index stations for arresting the feed of stock at that station; in the form shown, the stock feed-out station is that occupied by spindle l3. .Driving power for the spindles and for a forces are exerted on stock}! by drawing backa type wherein clamping collet-actuating tube 25. .The collets 24 may be conventionally actuated by means of grooved spools 26 which at the stock-feeding station may be engaged by a chucking or collet-actuating slide 2'! having a rocker-arm follower 28 to ride in the chucking slot 29 of a main cam drum 39 on the camshaft .21. The camshaft 25! may be rotated once for each indexed position of the spindle carrier, so that a chucking operation may take place for each indexed operation of the spindle carrier.

For stock-feeding purposes, I employ feedfinger means 3! at the forward end of a feed tube 32 within each collet, and the-finger pmtion 3! thereof is preferably as far forward as practicable. Feeding and withdrawing thrusts may be applied to the feed tube. 32 at the outer ring 33 of an anti-friction thrust bearing carried at the rear end of the feed tube. the form shown, stock 9 is supplied to the various feed tubes '32 :for the spindles from a stock reel mechanism 34 which is indexible with the spindlecarrier, as by connection to the spindle carrier by means of ;a;pin135 .(Fig. 3). The stock reel and various automatic features thereof may be as disclosed in my Patent No. 2,320 039, issued May 25 .1943.

Stock-feeding forces may be derived from the cam drum 39, as by a second profile 36 having a rise 3-! timed to cause retracting displacement of the feed fingers 3! just Eprior to an opening of the :collet 13; the cam, profile 36 may also include a feeding surface '38 timed for effectiveness while the collet jaws 24 are open. This feed motion may be translated from .cam drum 30 by the rocking -.of a feed lever .39 pivoted, as at 48, on the frame of the machine and including a follower roll 4| .to engage the said profile 36. The upper part of the arm .39 may .carry a second roll :42 for engagement with .aslot 43 in feed-slide ,means 44, .and shoe means 45- 15 carried by the feed-slide .means 44 may engage opposite sides of the thrust ring 33.

The feed-slide means 44 is .shown..guided by tvu'n .arbors ill-48 which may be anchored at both .ends .in the frame of the machine and which in the form shown extend to .the back plate 49 .of the machine; the Varbors 41-48 are also shown .slidably supporting the chucking or colleteac'tuating slide 21. A tension spring 15! may constantly urge the feed-slide :means 44 in a feeding direction so as .to force the follower roll 4 always to ride against the profile 35 of the cam 30; in the form shown, spring 5| is encased within arbor 48, anchored .at the vforward end toa fixed part (not shown) of the machine, and held at the other .end to a pinfiz carried by a part 54 of the feed-slide means 44. Pin 52, and with it the feed-slide means 44, .may be permitted longitudinal movement by means of longitudinal slot openings .53 in .arbor 48.

The roll 42 is preferably adjustably securable along the length of the upper part of lever 39, as .in a slot '391, so that the same .feed profile 36 may provide adjustable feeding displacements for the slide and, hence, for the stock. For further adjustment, the lever 39 may incorporate a secondfulcrum boss 50 :to receive'the pin 49. To assurethat the feed fingers 3i may always be as far forward as possible at the end of a feed stroke, no matter what the adjusted position of the roll 42 or of pin 40., the slots 39'43 may be designed for alignment with each other in'the fully -fed;position, as will be clear.

In accordance with the invention, I provide a means for automatically shutting down certain parts of the machine including the stock-feed mechanism, and preferably such other functions as spindle-carrier indexing, collet operation, and the like as may be controlled from the main camshaft :2l, whenever the stock 9 within any spindlehas been consumed to a point beyond which it is no longer considered useful; the shut-down means may be effective wholly at the feed-out stationthat is, while a given spin- .dle. is, at. the feed-out station, my mechanism may not only detect a shortage of stock in the said spindle but also shut down the camshaft soon enou h so the-thew stock may be loaded into the. said spindle without the need to wait foria succession of indexing operations, as has previously been the case. As an indication of this exhausted-stock condition, I employ means responsive to a disengagment of the feed-finger means 3! from a piece of stock 9 that is too short; such means may include a resiliently opposed lostimotion connection between the feedslide means 44 and the feed-finger means. .31., the connection being stressed for one of the strokes (feed or drawback) .of the feed-slide means 44. If there is .suiiicient stock 9 at the feed-out station, the frictional engagement of feed-finger means, .31 with the stock may be as great as to compel a take-up of the lost motion before said one. stroke can be effective, but if there is insufficient stock, the lost=moltion .may not take plane during said one stroke, and means responsive to the placement of, the lost-motion connection -.during said one stroke may ini iat the shut-down functions- In the form shown, the lost-motion connection is arranged to be effective durin the drawback stroke, and the shutdown functions may be initiated when or after the feed lingers .31 have slipped off the back end of a piec of stock 3 that is too short for further use. The lost-motion connection may include the drawback .shoa 4t, which maybe formed at the .end of an arm 55 pivotally supported on a rod or shaftifi JfQurnalled in the feed slide 44. The arm 55 represents a lost-motionelement "between the feed slide 44 and the feed fingers 9|, thelost motion being shown as an angular lostmotion, as illustrated in Fig. 5 in the displacement between the solid-line and dot-dash-line shapes shown. Resilient means may be employed to urge the arm 55 to a given limit of the lost motion, and in the form shown a spring 5?, which surrounds a shouldered rod 51' mounted within a part of the housing of the feed slide 44, normally urges a part 58 on arm 55 counterclockwise (in the sense of Fig. 5). For .each'feed of stock, the feed shoe '45 is solidlybacked byabutment at 45" with .the feed slide 44, so that upon abutment of shoe 4.5 with the thrust ring 5.3., ther may be positive encasem nt between the feed slide 44 and the feed fin er .31. For each drawback stroke, and as longas a ,sufiicient length of usable stock remains, the feed lin er 3| will be in tight dragging relation-with the stock so as to rock the-arm 55 clockwise in a compression of spring 5! and into a firm abutment, as by contact of abutment surfaces 55 (on arm 55) and 44' (on feed slide 44) with the shoe .46 assuming the dot-dash position of Fig. 5. If during the drawback stroke "the feed fingers 3| of 'a particularfeed tube 32 should slip off the end of the stock, the force of spring :51 is preferably sufficient to displace the shoe 46 through its lost motion travel to *take up the solid-line *position of Fig. 5, there being relatively little resistance then offered by the thrust ring 33. v

To initiate the shut-down functions in the form shown, a second arm 59 is clamped to the pivot shaft 56 for lost-motion rotation with the arm 55, and a pawl 66 at the end of arm 59 is poised to trip a declutching mechanism for the main camshaft 2! whenever the arms 5559 are in the solid-line positions of Fig. 5 during a drawback stroke. If there is usable stock 9 still to be fed, the drawback stroke may cause the pawl so of arm 59 to assume a displaced position out of possible engagement with the tripping mechanism, so that no declutching of the main camshaft need then result, as will be understood.

In the form shown, the tripping mechanism to be actuated by the pawl 60 on the arm 59 includes a longitudinally extending rack 62 supported by transverse arms, such as the arm 83, for pivoting about a longitudinal shaft 54. A latch-trip arm 65 may also be carried by the shaft 64, for dogging engagement with a latch member 68, which may be pivotally mounted on a longitudinally extending pivot axis 51. A tension spring 68' between latch members 6565 may serve to hold the latched position. When latched, as shown in Fig. 2, an abutment 69 on the latch member 65 may press the actuating button of a normally open electric switch H3 so as to hold the contacts thereof closed and to complete a circuit for closing a relay H, which in turn may control the actuation of a solenoid 12 (Fig. 8). The pawl (iii is preferably resiliently urged against an abutment Gil for assumption of a normal position (Fig. '7), so that positive coaction between pawl 59 and the disabling rack or bar 62 is possible only during a drawback stroke; to prevent possible actuation of rack 62 during a feeding stroke, the spring 68 holding latch members lie-66 together is preferably stronger than spring 68 for pawl Ell, so that pawl so may merely ratchet or ride on rack 52 during a feed stroke, as will be understood. It will be clear that, as long as there remains suf ficient stock to be fed, the trip arm with its pawl til will be thrust aside (to the extent of the lost motion in the mounting of arm 55) with each drawback actuation of the feed slide 44. This action. will mean that the pawl 63 may fail to engage the rack 62 and that the solenoid 52 may remain energized as long as there is usable stock 9 in the spindle at the stock feed-out station.

If desired, accurate alignment of the pawl 60 with rack 62 may be assured for the stated eventuality by providing for angular adjustment of the arm 59 on its pivot shaft 56. In the form shown (see Fig. '7), a collar 59 is anchored to shaft 56, and an oiiset portion or lug on collar 59 is adjustably engaged by screws 59" carried by arm 59, thus angularly orienting the arm 59 with respect to collar 59' and with respect to the drawback shoe 56, as will be clear.

When deenergized, the solenoid 12 may form part of a shut-down mechanism described in the above-mentioned patent for disengaging the main-camshaft clutch (not shown) and also, if desired, for applying braking means (not shown) to stop the main camshaft when the collet is open and ready to receive a new bar of stock. This shut-down mechanism is shown to include two arms l3'l4 pivoted at 15 and effectively disconnected as long as the solenoid 12 is energized. The arm 13 may follow a tripping cam 16 on the main camshaft 2 I, and the arm l4 may be in actuating relation with a rocker arm 11 in engagement with a spool 18 for shifting a clutch throw-out rod 9 for the main-camshaft clutch. In the form shown, the armature of solenoid I2 is linked by a rod 80 and by a latch rocker arm BI to an extended part of the arm 73, as at the pivot 82; and, as indicated, as long as-solenoid 12 remains energized, the motion of arm 13 in following the cam 16 may be purely wasted motion However, should the feed fin,- gers 3i slip off the end of a piece of stock during a drawback operation, spring 5? may cause a quick shift in the position of the pawl 69 from its neutral position (shown in Figs. 2 and 3) to its tripping position (shown in Figs. 4 and 5) and, therefore, into tripping alignment with the rack 62. Continued drawback of the feed slide 44 may force the rack to ride upon the pawl M and thus to raise the trip arm to the position of Fig. 4, for a release of the latch 66 and thus for an opening of the normally open switch It. The relay H will be immediately deenergized so as to permit spring 88 to draw rocker arms 8i13 into latching engagement, as against the notch 84 on lever 81. Upon the next rise of the cam-follower arm '13 on the cam 75, the members l3'M-5l will be effectively a solid body so as to enforce a clutch-disengaging shift of the rocker arm Ti to the left (in the sense of Fig. s).

It will be clear that by a proper setting of the timing cam it on the main camshaft 2! with relation to the collet-actuating profile .29 of the main cam 30, the feed mechanism (and for that matter all operations timed by the main camshaft 2!) may be shut down while the collet (of the spindle at the feed-out station) is open, thus facilitating manual removal of the unusable stock and reloading with a new bar. It will further be seen that since the drawback surface 31 of the feed cam 36 occurs immediate- 1y prior to the collet-actuating function, the feed fingers 3! cannot slip off a piece of stock until the last usable part thereof has been completely worked at all spindle stations, including the cut-off station. No indexing need, therefore, be performed (manually or otherwise) for a reloading operation, and a minimum of time is consumed in reloading.

Befor fully automatic operation of the machine is again possible, the latching members 65-455 must be reset, into a position to hold the switch I!) closed so as to disable the connection between trip arms l3-'i l. In the form shown, I provide for this resetting by means of a multipurpose manual-control arm or hand crank 35, which is shown accessible behind the rear plate d9 of the machine frame. The normal positioning of the control arm. or hand crank 85 (i. e. for

automatic operation) may be that shown in dotdash outlines in Fig. 2, and to condition the machine for restocking an empty spindle, such as the spindle It, the arm may be shifted to the dotted position 85 of Fig. 4. When shifted to the position 35 the arm 35 may, through a crank 8t and rocker arm ii'l, shift a control rod 68 to the third (9i of three detents 8--9t--9i, so as to engage and carry an adjustable abutment screw B2 on an upwardly projecting portion of lever 6t, thus shifting the latch arm it counterclockwise to permit arm $5 resiliently to reset the latch. It will be understood that when relatched in this manner, the abutment as on latch arm 66 may operably engage the electric switch HI to reenergize the solenoid l2 and thus to make 7? possible reengagement (as: by manuai. means ,I b; of, the. clutch tor the. main: camshait 2.1 .v

It has. been noted that the arrangement of. the tripping bar-or rack 62 may be. such that the feed meansmay be efiectively disabled should the feed. fmgers. become disengaged: from the stock: during any part. of the. drawback. stroke. The bar 62-. is preferably at least as long as the maximum feed stroke that maybe called for by adjustment of" lever 3S- and roll 42. The bar 62 may thus beconsidered as-a disabling means poised to operate whenever the-feed fingers run off the stock, regardless of the adjusted feed stroke. Moreover, the fact of adjusting the length of the feed stroke need have-no effect uponthe. readiness of the disabling means tooperate when there is no longera feeding engagement with the stock.

It has been indicatedthat the control crank 85'- may perform a number of functions and that, in the form shown, it may have three positions (see Fig. 4), each of which may be retained by oneof'the-detents 3599l One of these positions, namely, that shown in Fig. 2, may be termed the normal position, in which: fully automatic operation of the machine may proceed. A second position is shown in solid lines in Fig. 4 and may be termed the set-up or intermediate position, to be used when checking the setting of tools or for running the machine with a semiautomatic operation, as when feeding stock in one spindle only and stopping the machine after each index to check sizes, when setting up a new job or resetting tools after a smash up or other tool disturbance; The third and other extreme position 85 ofthehand crank 8-5 may be termed the restocking position (see Figs. 4 and 6).

'When restocking, and particularly when manually feeding a new piece of. stock into the feed fingers 3l for a particular spindle, it may be desirable that; the drive to the spindles be disengaged. In the form shown, this function may be accomplished by deenergizing the main motor. 94. for the machinewheneverthe hand control crank 85" is in the restockingiposition 8.5" (Fig; 4) For this-purpose, the latch-resetting-slide rod 38 may carry" an adjustable abutment screw 95 operatively toengage a second electric switch 96, which maybe of the normally closed variety. Thusfor the hand-crankv position. 85'', switch, 96 may be open so as to drop. out the. relay 9'! for the main motor 94; and thus to shut down the drive to the. spindles. After the new piece of stock has been loaded and the machine is again ready to run, it will be understood that by cranking the handle 85: into the, normal position. (Fig. 2) switch 96 may return to its normally closed position. A manually operated switch 96"in series with switch 9'5 may be used to start the motor 94 and the spindles, while the latch means, 65-66, having been reset; is. left ready to initiate another shutdown operation when the stock 9 in som other spindle may become exhausted.

In bumping stock; as during a manual restocking operation, the feed tube 32 should be bodily displaceable for a substantial part of the length of a spindle, s'o-that the new piece of stock and the feed tube 32 may b rammed forward against aforward abutment in the spindle. In the form shown, this forward abutment occurs upon. thrust ring 3% striking the drawback shoe 46,.and;upon take-up of the lost-motion in rocker arm 55; This sudden abutment may open the feedfingers 31: to permit the stock to extend forward-thereof; and the; bumping: out may have to be; repeated: several times over and until the stock extends. to the. stock stop 29; Thevwaymay be cleared for suchextended travel of the feed tube 30;, as for bumping-out operations, by alifting of the feed shoe: into the dotted position 45" of Fig. 4. lifting of the shoe- 45 may be accomplished as the handle 85 is shifted into the restocking. position 85 by positioning an abutment 58, on the feed-slide part 54 to operate a crank 99'. on. a. shaft Hill, the feed shoe 45 being. clamped to the shaft I00}. In the form shown, the: crank 99 is actuated by the abutment 98 through aslide pin I01: which may move in a guide boss H12 formed: in or carried by'the frame of the feed-slide means 64. The part 54 will berecalled as. the collar to which the pin 52 is secured; and, since the pin 52 is guided by the longitudinal slots 53 in the arbor 48, a rotation of arbor 48 will be understood to eifect rotation of the collar or slide part 54, whenever the handle 85 is actuated.

Under certain circumstances, as in the event of a breakage of the stock fced spring 5:1,. the forward or feedmotion. of slide 4:3 may cease before the full-forward position is reached. The ring. 33 of the feed tube 32' might then catch and ride under the drawback shoe 48 of the arm 55, so as to cause a counterclockwise rotation of arm 55 (in the. sense of Figs. 3 and 5). To anticipate this relatively remote contingency, means may be provided normally to: urge arm 55 clockwise, with its part against the shouldered part of rod 51 In the" form shown, this function is accomplished by means of another spring on rod 51 the spring 3! bein compressed between a stop nut and a slidabl'e washer 6!. Should there thenbe an obstruction, it will be understood that spring ti may serve to return the shoe 33 to its normal position when the obstruction has been cleared. The spring of may also serve usefully during abumpingout' operation, when it will be appreciated that the impact of ring 33' against the drawback shoe might (in the absence of spring 64) cause the shoe it to rebound in. a counterclockwise direction and, possibly, to ride over ring 33'; clearly, spring 51 may assure avoidance of this contingency.

In checking the setting of tools, as when setting up the machine or as after a crack-up in which sometools may have been damaged or dislocated, it may be desirable to operate the machine semiautomatically and to render the stock-feed function inoperative in all spindle positions but one. For such eventualities, I provide the intermediate position (solid outlines of Fig. 4) of the control handle In thisintermediate position, I employ a one-way engaging clutch mechanism whereby the feed-slide means M may be heldin a substantially drawn back position. The onewayclutching function may be effected by a pawl H33 and ratchet ltd, the pawl being carried by the collar member at 5%, and the ratch being in the form of a rack extending longitudinally to the back" frame plate 49; The rack Hi6 may be secured to the back plate 4901", as in the form shown, it may-pass through the plate 'iland carry any enlarged head it'd for resiliently urged abutment with plate 49.

It will be seen that in the intermediate position. of control handle. 8.5, the collar member 5 3 may be shifted to align pawl. H93. with the ratchet rack flit. (see Fig. 4)., and it. will be further appre ciated that if. the slide means to: is pulled back against the tension of sprin 5!, the ratchet mechanism may hold this retracted position; If desired, the.- forward; end ot. the ratchet bar tilt may carry a further abutment such as a washer held by a nut I05, and the ratchet bar I04 may thus serve to provide a forward limiting abutment means for limiting the forward travel of the feed slide 44. If the feed slide 44 is being held retracted by the ratchet mechanism, it will be clear that a mere shifting of the control handle 85 to either of its extreme positions may release the ratchet and allow spring M to carry the slide 44 forward either to the limiting abutment afforded by the nut I05 or to some position determined by the position of cam-follower roll M on the feed cam 36.

In a semi-automatic operation, it may be desirable to have the machine shut down the camshaft 2I (and, hence, all operations timed thereby) for each rotation of the camshaft 25. Such semi-automatic operation may be effected by a manual opening of a switch I in series with the normally-open switch iii and with the solenoid i2. Thus, with switch it closed and with hand crank 35 in its intermediate position, the stock-feed functions may be disabled (slide 44 held in drawn-back position by pawl Itt) while waiting for the spindle carrier Iii to index around to the desired position, whereupon switch '10 may be opened to shut down camshaft 23 (at the effective position of cam 16). In such case, the spindles will continue to rotate, and by throwing in the camshaft-clutch lever TI the camshaft may again be started; however, as long as switch Iii is open, the camshaft will operate only one revolution for each clutching operation of lever ii. After adjustments are made, the operator may move lever 35 to its normal or upper position, and the feed tubes 32 which had been effectively disabled will be automatically picked up again by the drawback shoe and by the feed shoe 55 as the tubes are automatically indexed to the feeding station.

If new stock has just been loaded into the machine or if there has been a semi-automatic operation of the machine, it may be that the spindles will have been rotating while the collet jaws have been open at the feed-out station. In such event, the stock 9 will have been loosely held in the collet for a short period of time, and the stock may walk backward a small amount from the desired fed-out position. If the collet jaws should then be clamped, and if the machine should proceed through a full cycle of indexed automatic operation, at least one piece of stock may have been so short as to require rejection.

In order to avoid this sort of difficulty, -I incorporate into the functions controlled by handle I 85 means for assuring the application of a final incremental holding thrust as the handle 85 is returned into its normal position (Fig. 2). In the form shown, this additional movement is derived from a small cam surface I06 in the formof a wedge formed on an offset part of the orwedge I06 is positioned for operative engagement with the headIIiiE at the backend of the rack bar I04. In Fig. 6, it will beseen that for the normal position (solid lines) of control handle 85 the cam or wedge surface I06 is out of engagement with the head member I05. Howboss It: for the handle crank 85, and the cam ever, forv the restocking position 85' of handle 10 be seen that the first function to occur as the control lever is moved from the restocking position 85' is the movement of the feed shoe 45 from the dotted-line position 45 to reengage the ring 33 of the feed tube; continued motion of lever 85 causes cam surface )6 to release its coacting member I05, thus permitting stock-feed spring 5| to hold a newly fed bar against the stock stop 20 (against which the new bar has been bumped) through the feed shoe 3?). This holding operation may take place after the spindles have been restarted and just before the collet jaws are closed, and the holding may be sufficient positively to urge the stock 9 against the stock stop it, thus assuring good initial use of the newly loaded stock.

For purposesof simplifying the drawings and the description, I have shown and described my invention in application to a single-index type of machine wherein each spindle is indexed a single station for each operation. It will be understood, however, that the presently described form may be readily applied to multiple-index machines, such as those which perform dup1icate operations simultaneously on two or more spindles and in which each index operation involves a spindle displacement of two or more stations. in the latter type of machine (i. e. a double-index machine), stock-feeding operations would take place simultaneously for two spindles, and in the form shown, the attachment of another feed shoe, such as the shoe 45, on the shaft 50% and in feeding alignment with the thrust ring 33 on spindle 52 would suffice. Similar simple modifications in the drawback and tripping mechanisms could be employed for application of the single feed-slide means 44 to a double-index machine, as will be clear.

It will be seen that I have described an ingenious mechanism for improving the efficiency of bar machines, particularly automatically indexed multiple-spindle bar machines. With the features provided by my invention there need be a minimum of time consumed in setting up the machine and in restocking a spindle in which the stock has been exhausted. My invention also provides assurance that stock will be consumed to the maximum extent possible. Simplicity of operation is assured by the employment of a multi-purpose single control means, with an incremental hold feature that may materially reduce the number of rejects due to insufficient feeding, following any interruption of automatic operation of the machine.

While I have described my invention in detail for the preferred form shown, it will be understood that modifications may be made within the scope of the invention as defined in the appended claims.

I claim: I

1. In an automatic bar machine or the like, a frame; stock-chucking means, stock-feeding means including longitudinally reciprocable feedslide means for feeding stock to said chucking 7 means, longitudinally acting resilient means urging said feed slidemeans in a stock-feeding direction, cam means in driving relation with said feed-slide means against the action of said re silientmeans for retracting the same, holding means including a part engaging said frame and including one-way-engaging clutch means effec tively engaging said feed-slide means a ainst the action of said resilient means and independently of the instantaneous position of said cam means,

manually operable meanscontrolling the opera! mascara? l1 tion-bf said clutch means, and means including a oam effective upon a displacement of said manually operable :rneans and before engagement of said clutch means to effect an incremental withdrawal of said feed-slide means, whereby in a position of clutch-engagement said feed-slide means may be held in an incrementally withdrawn position so that upon a return of said manually operable means to a position disengaging said clutch means said feed-slide means may chucking means carried by saidspindle, stock --feeding -means including a feed tube in saidspindle and longitudinally reciprocable feed-sl-ide means for feeding saidieed tube, feed meanscennected in feeding relation with said feed-slide means, said ieed-slide means including a yieldable abutment in driving relation with'said feed tube in a retracting displacement of the same, spring means carried by said feed-slide means and-opposingyieldable displacement-of said abutment with a force less than the -frictional grip of said feed tube on the stock but sufficient to move the'said tube in the absence of a grip upon stock, a latch and tripping means for s'aid latch, said tripping means including a longitudinally extending member --interceptable by said -abut merit member in an unyielded position thereof and clearing said abutment-member when said abutment -member has been yieldably displaced, whereby upon interception of said longitudinally extending member by said yieldable abutment member said latch may be'tripped, first disabling means for said feed means and positioned "to e'fiectively disable said feed-means upon a tripping of said latch, second disabling means for said drive means, and a single manually =o'perable resetting means for said latch, said manually operable means being manually-movable in a first-movement 'from a normal position to an abnormalpositionand actuating said second disabling ineans in such first movement, whereby said spindle may be stopped in response -to such first movement, said 'manually operable means being manually movable in a second movement from said abnormal position to said-no'rmal-p'cs'ition and being connected to reset said "latch means during said second movement, whereby upon said second movement of said manual means the functionsdisabled by both said-disabling means may be enabled.

4. In an automatic bar machine or the like; a spindle including a collet therein, feed-finger means for said spindle for feeding bar stock therein, longitudinally movable feed-slide means for said feed-finger means, cam means in controlling relation with said feedslide means and with said collet for operating said feed-slide means "and said collet in timed relation, retractable abutment means carried by said feed-slide means and drivinglyengageable with said feedfinger means in an extended position thereof, externally accessiblemanual actuating meansfor said retractable abutment means and including a longitudinally extending member, a longitudinall-y slidably keyed connection between said longitudinally extending member and said 'retractable abutment means, whereby said abutment means may be retracted by said manual actuating member for a plurality of ipossible longitudinal positions of said feed-slide means, dis- 'abling means 'for said cam means, said disabling means being connected "tosaid manual actuating means to eiiectively disable said cam means upon an actuation of -said manual means which also retracts said retractable abutment means, said disabling means and said abutment means being also so'connected tosaid manualactuating means that said abutment means is extended and said disabling means is rendered ineffective upon another operation of said manual actuating means.

5. In a'n automatic bar machine :or the like, a spindle including *a 'colle't, feed-finger means 1for feeding stock to said =co1let, cam means for operating I said collet and said f eed=finger means in =timed relation, longitudinally movable feed-slide means includinga follower for said cam means, movable abutment means carried by said slide 'means'andsaid feed-finger means and in a driving-abutment relation between said slide means and said feed-finger means in 'a retracting displacement of said slide, resilient meansc'arr-ied by "said slide means and urging said abutment means toward a fir'stiposition for abutment with said iced-finger means, whereby if said feedfinger means engages'stock for a-r'etracting stroke of said'slide'said resilient means may be-stressed through a lost motion represented by a movement of said abutment mea'ns to'a second position, "and whereby if said reed-finger means 'becomesdisengaged from the end of the-stock said resilient means may either prevent such lost 'inotion in'a retracting displacementof said'slide means or will cause return of said abutment means to "said first position immediately upon disengagement of said feed-finger means from the stock end, and longitudinally extending means positioned for interception by said abutment means When-said abutment means is insaid first position during 'a retraction -of said slide, said last-defined means being connected to disable said cam means when intercepted and being :positioned for no interception when said abut- 'ment means-is in said second position during a retraction of said slide.

6. In an automatic bar machine or 'the lik'e, a spindle including a collet, feed-finger 'ineahs ior said spindle for feeding bar sto'ck therein, longitudinally movable-'feed-slide means for said feed- -finger means, and a camshaft including cam means in controlling-relation with said feed-slide means and with said collet for operating said feed-slide means andsaid collet in timed relation, an abutment member-carried 'by said feedslide means and in lost-motion relation therewith for thrusting engagement with said feed- :finger means, resilient means carried by said feed-slide means "and "urging said member into a first given relation with said feedslide means, said abutment member being 'driven'a'gainst the actionof said resilient means to a second relation with I said feed=slide means upon thrusting against-said feed' finger ineans when said-ieedfinger means is engaging a fpiece'of stock, said resilient means being *sufi'iciently -strong to move said abutment means 'to said first relation when said feed finger mean's becomes disengaged from a .piece of -sto'ck, and longitudinally extendirfg camshaft-"disablingnieans responsive'tot he pos itioning of said abutment ine'rriber in said second relation for disabling said camshaft-when the position of saidmmber -reflets a-disengagement of said feed-finger means from the stock bein fed, said longitudinally extending disabling means being poised for actuation upon a movement of said abutment member through such lost motion, whereby immediately upon feed-finger disengagement from the stock there may be an actuation of said disabling means.

7. A machine according to claim 6, in which said member includes a shoe to abut said feedfinger means and a crank positioned in accordance with the position of said shoe, and in which said last-defined means includes latch means positioned to be tripped upon assumption of a given angular position of said crank and upon a given displacement of said feed-slide means.

8. In an automatic bar machine or the like, an

indexible spindle carrier, a plurality of spindles in said spindle carrier, collet means and a feed tube for each of said spindles for chucking and feeding bar stock therein, feed-slide means engageable with feed tubes successively indexed into a feed-out station for feeding the same at said station, cam means for actuating said collet means and said feed-slide means in timed rela tion at said station, a first abutment shoe carried by said feed-slide means for feeding abutment with a feed-tube at said station, a second abutment shoe carried by said feed-slide means for withdrawing abutment with said feed tube at said station, a lost-motion connection between one of said abutment shoes and said feed-slide means, means carried by said feed-slide means and urging said one shoe in the direction in which said one shoe is to be used for thrustin and with a force less than the frictional force of engagement of said feed-finger means with a 14 piece of stock, whereby said one shoe may be forcibly displaced through said lost motion for every movement of said feed-finger means in said direction as long as there is sufiicient stock to be fed so that said shoe may be in one of two positions relatively to said feed-slide means depending upon whether said feed-finger means engages the stock, and longitudinally extending means poised for actuation immediately upon a movement of said shoe to the position representing no stock engagement, said last-defined means being connected to disable said cam means, whereby said cam means may be disabled while the empty spindle is at the feed-out station so as to permit restocking without delay at the feedout station.

9. A machine according to claim 8, in which said lost-motion connection is between said second abutment shoe and said feed-slide means, whereby said cam means may be disabled after a withdrawal of said feed-finger means should said feed-finger means become disengaged from a piece of stock during such withdrawal.

ARTHUR H. J OBERT.

Montgomery et al. May 23, 1939 

